Liquid reservoir



FIG. 1 is a perspective view of the liquid reservoir showing our new design;

FIG. 2 is a front view in elevation thereof;

FIG. 3 is a right side view in elevation thereof;

FIG. 4 is a back view in elevation thereof;

FIG. 5 is a left side view in elevation thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines shown in FIGS. 1 through 5 are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a liquid reservoir, as shown and described above. 